With reference to FIG. 1 for a conventional artificial insemination tube for livestock breeding, the artificial insemination tube is mainly divided into two types, and each includes a sperm delivery duct 10, and a plug 20 installed at the front of the sperm delivery duct 10, wherein the plug 20 is an integral soft foam member and has a sleeve aperture 201 formed at the center of the plug 20 for installing and fixing the sperm delivery duct 10, an injection hole 202 with an appropriate length and a diameter slightly smaller than the front adjacent to the sleeve aperture 201, so that after the sperm delivery duct 10 are installed to the sleeve aperture 201, the front of the sperm delivery duct 10 will not be penetrated through or exposed from the injection hole 202. When an artificial insemination is applied to the livestock, the plug 20 is inserted slowly along the vagina of the livestock and entered into the uterus through the cervix, and then livestock semen stored in a semen bottle (or bag) is injected from the rear of the sperm delivery duct 10, and the injection hole 202 of the plug 20 enters into the uterus, so as to complete the artificial insemination procedure of the livestock.
Wherein, a soft plug 20 guided and entered into the uterus of the livestock reproductive organ has the effects of making the artificial insemination operation smoother and reducing the chance of injuring the reproductive organ. Undeniably, the soft plug 20 provides the aforementioned effects in applications, and thus is the most popular method used in the industry at present. However, the soft plug 20 still has the following drawbacks after a long time of use.
1. Since the plug 20 is an integral soft foam member, therefore the plug 20 enters into the vagina by pushing when the plug 20 enters into a female livestock body, and the front of the plug 20 is often compressed improperly, and the injection hole 202 may be deformed, decreased, narrowed, or even blocked. As a result, the artificial insemination efficiency is reduced.
2. Since the plug 20 is an integral soft foam member, the foam material (such as ethylene vinyl acetate (EVA)) for making the plug 20 is often foamed to a smaller density in order to maintain the overall softness of the plug 20, and the whole peripheral surface of the plug 20 is not of high density or smoothness. When the plug 20 is pushed and squeezed into the female livestock body, the operation is unsmooth, and sometimes even brings discomfort to the female livestock body.
3. Since the plug 20 is integrally formed and made by foaming a foam material, therefore the softness, hardness, and color of the plug 20 are fixed, and the scope of applicability of the artificial insemination tube is limited.
With reference to FIG. 2 for another conventional artificial insemination tube made of rubber, this artificial insemination tube comprises a sperm delivery duct 10 and a plug 20 integrally formed with each other and made of rubber, wherein the plug 20 is generally formed into a spiral shape and has an external diameter slightly smaller than the plug of the aforementioned foam member, which is a plug used for an artificial insemination tube. The spiral plug with a smaller diameter may be extended to a deeper position of the female livestock body to achieve the effect of a better hit rate of the artificial insemination, and such artificial insemination tube made of rubber has a relatively higher hardness, so that the injection hole 202 will not be deformed or blocked easily during the artificial insemination procedure. Since the plug 20 has a smooth surface, therefore it can enter into the female livestock body easily. However, the whole plug made of a hard material may bring discomfort to the female livestock body during the artificial insemination procedure due to improper operations or may even cause injuries, so that the application of such plug is usually restricted to professionals or technicians only and has the drawbacks of limiting its use by professionals and hurting the female livestock body. In addition the artificial insemination tube made of rubber comes with fixed softness, hardness, and color, and thus the scope of applicability is limited.